While expert systems are artificial intelligence (AI) agents, they share many common characteristics with human experts. As technology progresses, such systems are not just able to make simple decisions following "simplistic" linear logical protocols; they "behave" as real experts in at least two ways: by demonstrating superb decision-making skills and by conforming to the social norms for expertise, i.e., they "feel" as human experts. A review of the common characteristics of human experts may have important implications for the direction of the development for such systems. Implications for bioinformatics and future research (especially concerning the accompanying concept of "expert generalist") are also discussed.